The present invention relates to the field of bump stop devices used in particular on motor vehicles in the MacPherson struts of the steering wheels.
Conventionally, a bump stop is provided with a top race and a bottom race between which rolling elements and bottom and top retaining or support elements are placed such as covers, forming housings for the bottom and top races of the bearing respectively.
A bump stop is placed in the top portion of the MacPherson strut between a suspension spring and a top element secured to the bodywork of the vehicle. The suspension spring is placed around a shock absorber piston rod the end of which may be secured to the bodywork of the vehicle. The spring rests axially, directly or indirectly, on the bottom support cover of the bearing.
The bump stop therefore makes it possible to transmit axial forces between the suspension spring and the bodywork of the vehicle while allowing a relative angular movement between the bottom cover, which is movable in rotation, and the top cover. This relative angular movement may originate from a steering action of the steered wheels and/or from the compression of the suspension spring. For further details it is possible, for example, to refer to patent application FR-A1-2 822 508.
Also known from document FR-A1-2 901 737, is a bump stop provided with a support cover, a bearing mounted on the support cover and a subassembly for filtering the vibrations and for distributing stresses mounted against the support cover and comprising a vibration-filtering element as well as a stiffening strut mounted against this filtering element.
So as to allow the subassembly to be held on the support cover, the latter comprises a plurality of tongues forming stops interacting axially with the bottom end of said subassembly in the event of relative axial movement.
Such a solution may have certain disadvantages. Specifically, there is usually an axial clearance between the bottom end of the subassembly and the tongues of the support cover, which may cause slight relative axial movements between these two elements. In addition, it is necessary to provide a support cover with a relatively large axial dimension in order to allow the tongues to pass axially under the bottom end of the subassembly for filtering the vibrations and distributing the stresses.